:: deftheorem defines a_solution_of_Sierp169 NUMBER17:def 17 :
for s being Nat
for f being b₁ + 1 -element complex-valued FinSequence holds
( f is a_solution_of_Sierp169 iff Sum ((((f | s) (#) (f | s)) (#) (f | s)) ") = 1 / ((f . (s + 1)) |^ 3) );